Front End Software Engineer

The Software Engineer will play a critical role in both the sustainment of the current environment and the delivery of new user-facing capabilities. The selected individual will develop solutions to complex technical issues and problems that impact multiple areas or disciplines; regularly employ ingenuity and creativity to develop new technical solutions and systems to achieve functional objectives.

As a Software Engineer in Leidos, you will be immersed in one of our key programmes. On behalf of our central government customer, you will have direct impact on the current and future iterations of one of our most important pieces of critical national infrastructure.

This is a senior individual contributor role. The individual will be a highly experienced front-end engineer who leads through hands-on development, supports technical decision-making within their scope, and raises overall team capability through mentoring and technical guidance. Overall approach and architectural direction are agreed collaboratively with the Technical Lead and Software Architect.

Key Responsibilities

• Deliver high-quality, production-ready front-end software through hands-on development.
• Design, implement, test, document, and deploy modern single-page applications.
• Lead front-end implementation using React and TypeScript.
• Apply strong front-end engineering practices to ensure solutions are maintainable, modular, well-structured, and aligned with agreed standards.
• Make front-end technical recommendations within assigned scope, aligning with agreed architectural direction and escalating broader decisions as appropriate.
• Ensure adherence to established code review standards and quality gates for all front-end changes delivered.
• Continuously validate and maintain front-end build and deployment pipelines:

• Ensure changes do not break build, test, or deployment stages
• Make improvements as necessary to support reliable front-end delivery
• Act as a guide for other developers to ensure pipeline practices are understood and maintained

• Write and maintain unit and integration tests as a standard part of development.
• Support and contribute to UI and API test automation efforts, working closely with the test team (who retain ownership of overall outcomes).
• Collaborate closely with backend engineers to ensure clean separation of concerns and well-defined API contracts.
• Support Agile delivery practices, including planning, estimation, backlog refinement, and iterative delivery.
• Use and support development tooling and processes, including CI/CD pipelines and integrated security scanning.
• Mentor and guide other front-end engineers through code reviews, pairing, and informal technical coaching.
• Act as a senior technical point of reference for complex UI and front-end engineering challenges.

• Significant front-end engineering experience delivering production-grade single-page applications.
• Modern SPA development experience (required) using React and TypeScript, Angular, or Vue.
• Strong understanding of SPA design patterns and best practices, including component composition, state management approaches, and modular UI architecture.
• Proven experience delivering complex UI changes in production environments.
• Demonstrated experience writing unit and integration tests as a normal part of front-end development.
• Familiarity with Agile software development processes and working within iterative delivery models.
• Familiarity with the Atlassian tool suite (e.g. Jira, Bitbucket, Bamboo), or equivalent tooling, with a solid understanding of CI/CD concepts, workflows, and practices.
• Experience working with code review standards, quality gates, CI/CD pipelines, and security scanning processes.

Desirable Skills and Experience

• Experience working closely with backend teams on API-driven architectures.
• Familiarity with broader software design patterns beyond the front-end domain.
• Experience contributing to or supporting test automation initiatives (UI and/or API).
• Exposure to scripting languages (e.g. Python, bash) in support of tooling or build processes.

Pulled from the full job description

• Annual leave

• Company pension

• Private medical insurance

• Cycle to work scheme

• Work from home, At Leidos we are PASSIONATE about customer success, UNITED as a team and INSPIRED to make a difference. We offer meaningful and engaging careers, a collaborative culture, and support for your career goals, all while nurturing a healthy work-life balance. We provide an employment package that attracts, develops and retains only the best in talent. Our reward scheme includes:

• Contributory Pension Scheme

• Private Medical Insurance

• 33 days Annual Leave (including public and privilege holidays)

• Access to Flexible benefits (including life assurance, health schemes, gym memberships, annual buy and sell holidays and a cycle to work scheme)

• Flexi-Time Working, Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available at www.leidos.com/careers/pay-benefits.

Leidos UK & EUROPE - we work to make the world safer, healthier, and more efficient through technology, engineering and science. Leidos is a growing company delivering innovative technology and solutions focused on safeguarding critical capabilities and transformation in frontline services, our work in the United Kingdom includes addressing some of the most complex problems in defence, healthcare, government, safety and security, and transportation. What Makes Us Different: Purpose: you can use your passion and abilities at Leidos to keep the people you care about safe. We are at the forefront of machine learning, AI, cyber security and solutions. Using your skills in the technology frontline by helping to build a safer world. You can inspire change. Collaboration: having flexibility to do your job is one of our core benefits, enabling you to become part of our extraordinary team. We have been empowering our people to work flexibly for years. Whether you work from home, the office or on customer sites, we will give you the digital tools and the flexibility to work smarter and align your needs and ours. People: Leidos empowers people from every background to be themselves and gives you the tools to learn new skills by enabling growth whilst developing. We believe that extraordinary people need opportunities to grow, to be inspired and to inspire others. At Leidos, we invest in technical academies, career rotations and a career development plans that enhance your future. If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo - because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 - and moving faster than anyone else dares., Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit www.Leidos.com.